The U.S. Steel plant in Clairton, Pa., where an explosion killed two workers and injured 10 on Monday, has a history of maintenance issues, explosions and environmental violations.
The Clairton Coke Works, located about 15 miles south of Pittsburgh, is the largest coke plant in North America, producing 4.3 million tons a year, according to the company. Coke, a key component of steel making, is produced by baking coal at very high temperatures. One of the top byproducts is coke oven gas, a flammable mixture of gases that the company also uses as a fuel source.
The coke is baked in ovens, which are grouped into batteries. Batteries 13 and 14 each have 61 coke ovens, according to company documents. Each oven is a tall, thin chamber where coke is baked at over 2000 degrees Fahrenheit for hours. After the coke is made, it is pushed out of the chamber and quenched. The company then transports the coke to other steel mills, where it is part of the process to convert iron ore into steel.
The coke plant has had a number of high-profile accidents in recent years.
In 2009, a worker, Nick Revetta, died in an explosion at the plant. In 2014, another worker died in a fall.
In 2010, an explosion injured 20 workers at Clairton.
'One of the most decrepit facilities I've ever seen'
In 2018, a Christmas Eve fire knocked pollution controls out for three months at the plant. The loss of pollution controls led to a 4500 percent increase in sulfur air pollution from the plant. Asthma cases in the area surged, studies have shown.
Investigators concluded that the fire was caused by the failure of multiple pieces of corroded equipment.
In a 2020 deposition given after the fire, Jim Kelly, former deputy director of environmental health at the Allegheny County Health Department, said that he toured the facility in 2017 and found it "one of the most decrepit facilities I've ever seen in my nearly 30 years of work." Kelly said the facility had "lots of rust and unused equipment, and just generally … poor conditions of a lot of the equipment there."
More recently, an explosion at the plant in February sent two workers to the hospital, and a malfunction in June knocked out the plant's pollution controls.
Air pollution violations
On top of accidents, the plant has been a serial violator of air pollution regulations.
Since 2022, the Allegheny County Health Department has fined the plant $56 million for air quality violations, including a $42 million settlement for the Christmas Eve fire. The most recent fine of more than $900,0000 included violations at batteries 13 and 14, where Monday's explosion occurred.
The plant has violated the Clean Air Act in each of the past 12 quarters, according to the EPA, and is by far the largest single source of air pollutants in Allegheny County.
At a press conference on Tuesday, U.S. Steel officials said the plant was operating normally and the company was investigating the cause of the explosion.
U.S. Steel was recently purchased by Japan-based Nippon Steel. Nippon has pledged to spend $2.4 billion on U.S. Steel's Mon Valley Works, which includes Clairton and two other plants near Pittsburgh. Local environmental groups say that level of investment means the company can afford to clean up the facilities.
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